Science: it works, bitches!

[Supergrunch]

Best dissection I've done was of a whole rat. It was a pretty big one too.

[Strider]

Best dissection I've done was of a whole rat. It was a pretty big one too.

 

Funny you mention that, i'll be doing it this coming friday.

[Blackfox]

I'm on kidneys atm.

Disecting one next week.

 

Human...?

[Ginger_Chris]

Last time I did a dissection:

 

Pupil: "Sir, isn't blood poisonous"

Me: "Yes. Yes it is"

Pupil: *runs over to sink and starts scrubbing her hands vigorously*

 

When will they start teaching children sarcasm as part of the curriculum?

 

I don't pretend to understand this in depth - I read it in a popular science book somewhere. Anyway, the papers vary in comprehensibility - the abstract of this one makes some sense. You'll be shocked (:wink:) to hear that I switched from physics to evolution a few weeks ago, methinks I'll go into biochemistry or genetics.

 

Still isn't clear that they slowed the pulse of the actual photons. Silly physicists.

 

I'm not that shocked actually, if I could have chosen a different degree i would have liked to have done zoology or evolutionary biology. Might have been a bit to much stats for my liking though, but i know where your coming from.

[Supergrunch]

I'm not that shocked actually, if I could have chosen a different degree i would have liked to have done zoology or evolutionary biology. Might have been a bit to much stats for my liking though, but i know where your coming from.

Well, what with natural sciences being as it is, I'm also studying biology of cells, chemistry, and behaviour, and differential equationy things. I just changed from the physics module... it wasn't such a good idea to do it without a physics a level, and I think I'd rather do biology.

[system_error]

Fun with science:

 

You are candidate in a quiz show. The grand price is a sportscar. There are 3 doors and you have to select one where you believe the car is behind. So one door has a car behind it and the other 2 doors goats.

 

 

You select a door then the quiz master opens one of the other doors. And that door has always a goat in it. Now you can select again ... do you stick with your choice or do you change? Does it matter at all ?

[Shino]

Fun with science:

 

You are candidate in a quiz show. The grand price is a sportscar. There are 3 doors and you have to select one where you believe the car is behind. So one door has a car behind it and the other 2 doors goats.

 

 

You select a door then the quiz master opens one of the other doors. And that door has always a goat in it. Now you can select again ... do you stick with your choice or do you change? Does it matter at all ?

 

Hmm, I've seen this in NUMB3RS. Can't remember though.

[Supergrunch]

Fun with science:

 

You are candidate in a quiz show. The grand price is a sportscar. There are 3 doors and you have to select one where you believe the car is behind. So one door has a car behind it and the other 2 doors goats.

 

 

You select a door then the quiz master opens one of the other doors. And that door has always a goat in it. Now you can select again ... do you stick with your choice or do you change? Does it matter at all ?

Change, it gives you a better chance.

 

Can't remember the proof though, go ahead and post it.

[weeyellowbloke]

Fun with science:

 

You are candidate in a quiz show. The grand price is a sportscar. There are 3 doors and you have to select one where you believe the car is behind. So one door has a car behind it and the other 2 doors goats.

 

 

You select a door then the quiz master opens one of the other doors. And that door has always a goat in it. Now you can select again ... do you stick with your choice or do you change? Does it matter at all ?

 

I doesn't matter, even if you choose wrong you don't loses anything and will still have a goat. So it's basically a 50/50 gamble between two doors in which you might not win anything but you certainly wont lose anything so go for it.

[Supergrunch]

I doesn't matter, even if you choose wrong you don't loses anything and will still have a goat. So it's basically a 50/50 gamble between two doors in which you might not win anything but you certainly wont lose anything so go for it.

That's the thing, it's not 50/50. The probability of winning a car is 2/3 if you switch, so it's always better to do so. This is a result of the quiz master knowing what is behind each door such that he won't reveal the car by mistake.

 

To see why, let's look at the possibilities if the quiz master doesn't know what's behind each door. (i.e. he may reveal the car by mistake)

 

Player chooses

host reveals

remaining door contains

Goat A

Car

Goat B

Goat B

Car

Goat A

Goat A

Goat B

Car

Goat B

Goat A

Car

Car

Goat A

Goat B

Car

Goat B

Goat A

 

So the chance here is 50/50. However, the quiz master cannot reveal a car, so he knows what is behind each door, and is constrained in the cases where he would usually reveal a car. This leads to the following possibilities:

 

Player chooses

host reveals

remaining door contains

Goat A

Goat B

Car

Goat B

Goat A

Car

Goat A

Goat B

Car

Goat B

Goat A

Car

Car

Goat A

Goat B

Car

Goat B

Goat A

 

So there is a 2/3 chance of winning if you switch.

 

This seems completely irrational to most people (myself included) - I think when it was first pointed out a great deal of maths professors complained, but it is now agreed that this is correct. Probability can be odd.

[Shino]

I didn't understood in NUMB3RS and I still don't get it now.

[Zell]

Grunchie is right. If you change, the probability is two thirds. I saw this a while ago.

 

A few days ago I stumbled across this countdown numbers game.

 

952 - 100, 75, 50, 25, 3, 6

 

There is a solution for this but it's not that obvious. In fact, it's bloody difficult.

[system_error]

Explaination is easy:

 

3 Doors - when you first choose a door you have a chance of 1/3 to get it right. When you have to change again your chance is 2/3 instead of 1/3 because one door with a goat has already been eliminated.

[Stalin]

So should you swap your box at the end of Deal or No deal?

 

I do love that programme, even if it does represent everything I hate about the world. I think it's that Noel Edmonds. Oh boy, does he do it for me. I mean, erm...

 

Fuck.

 

I like to have sex with women. Yes.

[Domo Kun]

I really can't do science. I don't understand it at all. When comfronted with anything scientific I feel immense head pains.

 

What I'm interested to know is is there actually any hard proof for the big bang? It sounds a lot more plausable than the 7 days theory, but (keep in mind I don't understand science at all...) it really does sound like a bunch of bullshit to me.

 

I expect to get a hoard of angry replies for saying that

 

 

Oh and I got a C at GCSE. I stuck with social science.

[Sheikah]

An easy way to interpret the goat thing...

 

You have a 2 in 3 chance of picking a goat at the start. The host will then show the other goat. Therefore by switching using this method you will have a 2 in 3 chance that the door you switch to will be a car, because of the 2 in 3 chance of picking a goat.

[system_error]

I really can't do science. I don't understand it at all. When comfronted with anything scientific I feel immense head pains.

 

What I'm interested to know is is there actually any hard proof for the big bang? It sounds a lot more plausable than the 7 days theory, but (keep in mind I don't understand science at all...) it really does sound like a bunch of bullshit to me.

 

I expect to get a hoard of angry replies for saying that

 

 

Oh and I got a C at GCSE. I stuck with social science.

 

My life gets owned by maths every day....

 

But it was my choice solving equotations, creating efficient algorithms and calculating electronical networks. I hope it pays of some day and I get a decent job

[Supergrunch]

I really can't do science. I don't understand it at all. When comfronted with anything scientific I feel immense head pains.

 

What I'm interested to know is is there actually any hard proof for the big bang? It sounds a lot more plausable than the 7 days theory, but (keep in mind I don't understand science at all...) it really does sound like a bunch of bullshit to me.

 

I expect to get a hoard of angry replies for saying that

 

 

Oh and I got a C at GCSE. I stuck with social science.

The best evidence is cosmic microwave background radiation, a result of red shifted light from the big bang itself. In fact, the title of this topic is a reference to how beautifully the observed data fits the theory:

 

 

The error bars on this curve were too small to draw at this resolution.

 

Further evidence is given by the fact that distant galaxies are also red shifted, suggesting that the entire universe is expanding, seemingly a result of a massive explosion. (this also had an alternative explanation - that everything was moving away from the Earth, but more complex measurements have disproved this perspective)

 

There is more evidence than this, but these are the main two pieces. As a result of this evidence, all the competing theories were rejected, including the steady state theory. In fact, Fred Hoyle, the creator of the steady state theory, claimed it was the case until he died, and indeed coined the term "big bang" to lampoon the competing theory. Perhaps this is partly why it seems silly to you.

[Ginger_Chris]

Cosmic microwave background (CMB) radiation is the photons that last interacted with something during 'decoupling'. Before decoupling, the mean free path of light was tiny (ie it bumped into stuff every few centimeters), and electrons had so much energy they didn't orbit protons. It was a hot dense gloopy mess of photons, electrons and neutrons, and everything was the same temperature because they bumped into each other so often.

 

As this expanded it cooled. When it reached 3000K (still hot by our standards), the electrons started orbiting protons, and so light stopped scattering off all the free electrons. This happened about 400,000 years after the big bang. Its called decoupling because it's when matter and energy were no longer in thermal equilibrium (the same temperature). The CMB we observe are the photons that last interacted with an particle all that time ago (about 13.6 billion years ago) and has been travelling ever since. During that time, space itself has expanded causing the wavelength of the photons to increase and correspond to a temperature of 2.725K, rather than the initial 3000K (the photon kinda got stretched out as space expanded so it looks less energetic that it originally was).

[Supergrunch]

Cosmic microwave background (CMB) radiation is the photons that last interacted with something during 'decoupling'. Before decoupling, the mean free path of light was tiny (ie it bumped into stuff every few centimeters), and electrons had so much energy they didn't orbit protons. It was a hot dense gloopy mess of photons, electrons and neutrons, and everything was the same temperature because they bumped into each other so often.

 

As this expanded it cooled. When it reached 3000K (still hot by our standards), the electrons started orbiting protons, and so light stopped scattering off all the free electrons. This happened about 400,000 years after the big bang. Its called decoupling because it's when matter and energy were no longer in thermal equilibrium (the same temperature). The CMB we observe are the photons that last interacted with an particle all that time ago (about 13.6 billion years ago) and has been travelling ever since. During that time, space itself has expanded causing the wavelength of the photons to increase and correspond to a temperature of 2.725K, rather than the initial 3000K (the photon kinda got stretched out as space expanded so it looks less energetic that it originally was).

That makes more sense... but anyway, there's currently more evidence for the big bang than for any other theory, which is why it's currently accepted. Because that's how science works, though some people don't seem to think so.

[Demuwan]

Chemistry got more awesome now we're doing A2. A few weeks ago we were handling 18M Sulphuric Acid (nasty stuff). Today we determined the melting point of the aspirin we made.

 

What exam board are you doing.

[Supergrunch]

What exam board are you doing.

Sounds like something better than OCR Salters. Even doing university chemistry (part of my course) I haven't got to use acid anything like that strong.

 

However, in my evolution practical today I did get to freeze leaves in liquid nitrogen before crushing them. And they let us use chloroform... apparently in the group before us, it got spilt is someone's lap.

[DomJcg]

ok...can anyone prove dark matter?

[Supergrunch]

ok...can anyone prove dark matter?

I doubt it - isn't that just the current theory explaining the disparities in mass between two different methods for measuring the mass of the universe?

[Blue_Ninja0]

ok...can anyone prove dark matter?

 

What? I think it's pretty much proved. I think it can be artificially produced in laboratory and sustained in very small quantities and only for a few instants.